I have a question in regards to the Super Mario event music selection data: How do I rearrange it all, y'know, in the same way as I would the area music selection data?

For the area music selection change, you simply revise the byte at address 0x1121 and also the byte at address 0x1122 if necessary (these being the last two bytes in the absolute LDA,Y instruction - which tells the ROM to take the address at 0x10F7 and add the present bit in the Y register, and then store that particular value in the A register - represented under byte $B9).

Byte $FB (in the zero-page STA instruction represented under byte $85) is the opcode for the area music queue; while byte $FC represents the event music queue. And to get the other, I changed the default byte located at address 0x1124 to $FC; and that was why I was able to get all the area songs replaced with all the event songs (cf.: instead of hearing the ground level music playing you hear the death music; the dungeon music is replaced by the victory music; the water music is replaced by the standard Game Over music; and so on).

Event music selection data:
Silence - %10000000 ($80)

TimeRunningOutMusic - %01000000 ($40)
EndOfLevelMusic - %00100000 ($20)
AltGameOverMusic - %00010000 ($10)
EndOfCastleMusic - %00001000 ($08)
VictoryMusic - %00000100 ($04)
GameOverMusic - %00000010 ($02)
DeathMusic - %00000001 ($01)

~Ben

There's an editor in Japanese that'll help you edit the music. I wish it were translated, but if you wanna take a look at it, it's here. It's the music12.zip file.

Nobody is going to do this for you, Hamtaro126.

Hamtaro, do you know any docs for SMB2 (DDP) hacking, or someone who has actually worked with its music segment?

I'm surprised I never knew about Data Crystal. Thanks!